Microsoft Teams External Vishing & Impersonation Detection
Detects external Microsoft Teams calls involving screen sharing and impersonation of trusted entities. This rule identifies high-risk credential theft or RAT installation vectors by filtering for calls where screen sharing occurs and the `identity_name` (likely the external caller's domain or display name) matches patterns associated with free/abused TLDs, cheap/throwaway TLDs, phishing-common TLDs, high-risk specialty TLDs, PHaaS kit TLDs, or impersonates common trusted entities like 'microsoft', 'helpdesk', 'it.support', 'admin', 'security.team', 'apple', 'google', 'amazon', 'paypal', 'bank', etc.
Cortex XDR
